Java has fallen off the top spot in Tiobe's monthly index on the popularity of programming languages, giving way to C in the April report released this week.

C was being used by 17.555% of developers in the Tiobe Programming Community Index for April while Java was used by 17.026%. Last month, Java was used by 17.1% of developers while C was used by 17.09% of developers.

While Java has dominated the index over the years, it has slipped out of the top spot before. Java has been the top language in the index since 2001 with a few exceptions between mid-2004 and mid-2005 and couple of months in 2010.

"It took some time but Java's long-term downward trend line finally crosses C's stable (almost flat) popularity line," Tiobe said in its report this week. "Although it is expected that Java will not decline much further due to the popularity of the Android platform, C is able to remain number one for at least another couple of months. This can be concluded by looking at the extrapolation of moving averages for both languages."

Tiobe also cited other interesting moves this month as the entrances into the top 50 of Visual FoxPro, coming in at number 42; Scala, at 45 and Alice, ranked 48. Exiting are Eiffel, PL/I and Tcl. The index gauges the number of skilled engineers worldwide, courses and third-party vendors using a particular language, and ratings are determined through assessments of popular search engines such as Google, Bing and Yahoo as well as other sites such as Wikipedia, Amazon and YouTube.